No; I'm hoping for June tickets, too, and the prices stink!
Farecompare used to have a feature where you put in the trip location (BZE), and it would show the top 20 or 50 fares from various cities across the US. I can't seem to find that now, though.
Also, Hotwire lets you search a 30-day time frame, so if the dates are flexible, that can be a good site.
I'll keep an eye out for these cities, if you keep an eye out for a sale from St. Louis!